There isn't nearly enough sloganeering in pop these days, but Planningtorock's new album All Love's Legal has it down to a fine art. "Fall in love with whoever you want to," runs its subtly pro-gay opening mantra. "Patriarchal life, get out of the way!" she sings on Patriarchy Over & Out, in the manner of a haughty disco diva washing a no-good man right out of her hair. And if you didn't quite get the message, there's the confoundingly funky Misogyny Drop Dead. Feminism has rarely sounded so much fun.

"I wanted to find a way to write about these issues without making anyone feel like they're being negatively confronted," explains Jam Rostron, the Berlin-based Boltonian behind the Planningtotock moniker. "So I set myself an exercise to write about patriarchy in a really simple way. What do I think about it? I just don't want it to be there, I want it to get out of the way. So why not just say that? It is very simple, to the point where it's actually a little bit funny. Which is perfect, because I don't want people to feel threatened. It is a complex, heavy topic but I didn't want to be fearful."

Pop songs are the perfect medium for putting across political ideas in a pithy, humorous way, but when's the last time you heard anyone do that? "Titles of tracks and albums are absolute opportunities," agrees Rostron, "and yet there are so many at the moment that don't say nothin'. Wolf blah de blah? Who cares, you know? I've never really been a big Smiths fan, but then I came across Meat Is Murder; that's what you can do with a title."

We're in a queer bar in Berlin's Kreuzberg district, where Rostron's lived since 2002 after finding the city's cheap rents and lively cultural mix more welcoming than anywhere back home. "I've never really felt particularly English, whatever that is. I do like England, I go back and see my family in Bolton every Christmas, but I prefer the idea that you're not really English or French or Spanish. You are who you are and you can look for the culture that suits you."

Originally a video artist, Rostron says she got "completely freaked out by the art world because it's so elitist and ungiving. Whereas the great thing about music is that everybody feels they can own it; it doesn't need to be validated by any institute." Once in Berlin, she was encouraged to concentrate on music by punky electro outfit Chicks On Speed (who put out her first album, Have It All, in 2006) and Peaches (who took her on tour). Her second album – the murky, cryptic W – came out on DFA in 2009 after Rostron was headhunted by James Murphy, although Rostron is ambivalent about it today. "It's a nice record, but there's lots of nice records out there. I had to ask myself: 'What do I want from music?'"

The answer came to her in the form of Let's Talk About Gender, Baby – built around a line from her friends the Knife's Full Of Fire – with its forthright message and inclusive disco pulse. "I definitely wanted that to be an outright, shameless disco track. I thought it was the right sonic environment for those lyrics; they're really direct and simple, it could even be karaoke. And I liked the reference to the history of disco and its queer roots."

'Just because I don't want to be sexualised doesn't make me asexual. It is a real dilemma: because of the culture we live in, women very quickly get objectified. But I think women should be as sexual as they want'

Around the time of writing these songs, Rostron also officially changed her first name from Janine to Jam in order to "de-genderise" it. ("I've been Jam or Jammy or Jammers for a while," she explains. "Not even my mum calls me Janine.") It's one of a number of strategies she's employed to protest at the way women in music are still objectified, patronised and belittled. Like the Knife, she often plays around with her voice, so you can't tell if it's a man or a woman singing. She prefers not be photographed directly, and for the W tour she disfigured her face with prosthetics. "If you change the size of your brow then it's hard to tell what gender you are. I made these different faces out of silicon that I'd stick on with theatre glue. It was fun going through airport control… Then the whole show I'd be fretting about them falling off."

Even so, some reviewers missed the point. "I got called asexual," she says. "But just because I don't want to be sexualised doesn't make me asexual. It is a real dilemma for women on stage. Because of the culture we live in, women very quickly get objectified. But I think women should be as sexual as they want, they shouldn't have to censor themselves."

We're joined at the table by three of Rostron's friends and collaborators: bandmate Hermione Frank (who also makes minimal house music as rRoxymore), techno producer Paula Temple and Tunisian musician Houwaida Hedfi. All have numerous tales of being patronised by soundmen or male studio technicians, even in ultra-liberal Berlin.

"Gender discrimination is fucking boring," sighs Rostron. "You're like, 'Here we go'. It's a ritual of having to prove yourself all the time." She used to get angry; these days she just brings her own sound engineer. In fact, everything on All Love's Legal, from production to label duties, was overseen by Rostron or one of her likeminded inner circle, in order to circumvent the usual blokey channels. Any compromises in sound quality – and Rostron says she'd love to make a "proper disco album" one day, with full Chic strings instead of digital plug-ins – were justified by showing that it can be done.

"I try not to get cynical or browbeaten," says Rostron, a tough, positive outlook that shines through on her album. "It's still flabbergasting when [gender discrimination] happens to you. But things are changing." Patriarchy, over and out.